OSB vs Plywood

Choosing the right material for your home’s flooring is not always straightforward. There are a number of choices available. If you prefer a wooden material, there are two popular materials that people usually choose, which are oriented strand board (OSB) and plywood. Over the years, the popularity of OSB has steadily risen up – it now has more market share than plywood. Still, they have different pros and cons, so make sure that you understand the differences between OSB vs plywood in order to determine the best choice for your home.

What is OSB?
Oriented strand board (OSB) is a rectangular piece made from wood strands that are layered in a specific pattern and are combined together by using wax and resin adhesives. You see, while plywood uses wood veneers, OSB is composed of at least 50 layers of large wood flakes that are arranged to form a single sheet. The outer layers are set parallel to the panel’s strength axis, while the inner layers are put perpendicular to the axis. Compared to plywood, OSB is a new building material. OSB is most commonly used for subfloors, walls, and roofs.

Pros and Cons of OSB
OSB tends to be cheaper than plywood, but note that the price of OSB has increased in the last few years due to the increasing popularity. OSB is usually produced as large sheets, so the sizing can be more easily done. You can use a single sheet to sheath a large area of a wall or the joists.

OSB is very good for webs of wooden joists due to the much higher shear value. It does not have soft spots formed from overlapping knot holes. As the effect, it can be nailed at the edges and corners without any worry about such soft spots. While it lacks the look of natural wood grains, it has smooth surfaces on both sides, making it easier to work with. OSB is relatively greener and more environment-friendly because the flakes are chipped out from smaller trees.

However, OSB is not as stiff and sturdy as plywood. Since it has waxes, adhesion will not work well on it. OSB vs plywood tends to be heavier and more prone to swelling. And, compared to plywood, OSB’s water resistance is worse.

What is Plywood?
Plywood is made of thin veneer sheets that are compressed and glued together into a single piece. It has great structural strength, thanks to the perpendicular layers. The veneer sheets are put back and forth to create a cohesive sandwich which is very sturdy and stable. (Read also : Drywall vs Plywood)

When looking for plywood, make sure that you choose a product that has the “AC” grade. It means that the product has an “A” side (sanded and smooth) and a “C” side (rough and knotty). You are going to install the plywood product with the rough, knotty surface facing down.

Pros and Cons of Plywood
You should choose plywood when stiffness and structural integrity are top priorities. For example, for the subflooring under ceramic tiles, you need something that doesn’t flex – any flex will cause cracking in the tiles and grouts. For such case, you want to use plywood.

The appearance may not matter if the plywood is going to be covered up. However, if the surface is going to be exposed, plywood has the better appearance. It has true wood grains that look elegant and classy. Plywood is excellent for adhesives, and it is more resistant to swelling.

Plywood is not completely waterproof. But, compared to OSB, it is more resistant against water and moisture. So, it is a more suitable choice for places that have to withstand slight humidity.

There are just a few disadvantages about plywood. It tends to be more expensive, and it may require some more works. This is especially true if you need to install huge panels. The available plywood products usually don’t come in very large sizes.

Conclusion
OSB is great if you don’t need to worry about moisture, swelling, or adhesion. It tends to be cheaper, and there are huge panels for large-sized installations. However, choose plywood if you need to prioritize stiffness and structural integrity. Plywood has better resistance to moisture and swelling, and is great for adhesives.